The Great Auks had no natural predators and therefore, no natural fear of humans. While Auks were very fast and agile swimmers, they were large and clumsy on land. Auks were soon hunted on a large scale for food, their eggs, and even their downy feathers. Sadly the last pair was killed in 1844 and the Great Auk became extinct.
Today there are 17 species of penguins living and breeding in the Southern Hemisphere, which may have helped spare them the same fate. Penguins face challenges throughout their home ranges. Relatively warm weather species like the Galapagos and Humboldt penguins can live as far north as the Equator. While the hearty giants of the Antarctic, the Emperor penguins reside virtually on the South Pole.
Penguins are perhaps the most social of all birds. These birds of a feather flock together in colonies throughout the Antarctic islands. Sometimes these rookeries attract hundreds of thousands of penguins in one place. Like other birds, many penguins are nest builders. Some species dig out burrows for their eggs, while other species use available rocks, twigs and feathers for hatching their offspring.
But penguins have one main difference from the rest of their feathered friends; bone structure. For birds that spend most of their time in the air, a lightweight and sturdy bone is needed. Diving birds have strong bones, but penguins' bones are heavier so they don't have to fight the tendency to bob back to the surface. Even though their wings are useless for venturing into the sky, don't feel sorry for the penguin. They spend a majority of their time "flying"Â through the water sometimes at speeds up to 30 miles per hour. A penguin's body is streamlined for zooming through the water - the flippers providing the speed, the feet and tail used for steering and braking. Not only are they great at maneuvering underwater, some penguins species are like tiny submarines. Gentoo penguins for example, can stay underwater for up to seven minutes and reach depths of nearly 330 feet.
Most penguins are cruising for food while they are in the water. Krill, squid, and fish make up the bulk of their diet. Generally penguins look alike. Their black and white color scheme is actually great camouflage. Their breasts are bright white to blend in with the sky when seen from below, while their backs and tails are black to mask their identity when seen from above. But look closely and you'll see that's where the similarities end. Height ranges from the giant Emperor penguin standing nearly 4 feet tall, to the Fairy or Little Blue penguin which grows only to a height of around 16 inches. Marking and coloration varies between the various penguin species as well.
Megadyptes: There's only one; the yellow eyed penguin. These birds not only have yellow eyes, they also have a yellow stripe that runs from one eye around the back of the head to the other eye.
Eudyptula: The Little Blue or Fairy penguin is easily identified by its size and color. As the name implies, this species is the worlds smallest and has pale blue or gray blue shading.
Aptnodytes: The Emperor and King penguins are not only easily the largest species; they also can be identified by their colorful feathers and slender beaks.
Spheniscus: Humboldt, Galapagos, and African penguins are members of this genus. They are the "warm"Â weather penguins that have thick sturdy beaks and stripes running down their bodies.
Pygoscelis: The genus that includes Adelie, Chinstrap, and Gentoo penguins. These are the classic black and white penguins often featured in animated films and cartoons.
Eudyptes: These are the crested penguins and include the Erect-crested, Rockhopper, and Macaroni species. Their yellow plumage above the eyes make the crested penguins stand out in a crowd.
The "Penguins' Rock"Â exhibit at the Tennessee Aquarium will feature Gentoo and Macaroni penguins.
These particular species cannot be seen at any other zoo or aquarium in the region, and were chosen for their lively nature. Gentoos and Macaronis also pair up well on exhibit, so the expectation is "Penguins' Rock"Â will be a place to visit again and again to see penguin chicks hatching and growing in the future. -- www.tnaqua.org